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Report on the Technical Inspection of Industrial Boilers in the United States – Chinese Delegation for Industrial Boilers under the TCAPP/CATETC Project, November 2002. Introduction: In accordance with the requirements of the “Technical Cooperation Agreement Pilot Project” (TCAPP) and the “Clean Air and Clean Energy Cooperation Project,” a nine-member delegation from China’s TCAPP/CATETC project, at the invitation of the U.S. Environmental Protection Agency (EPA), visited the United States from October 21 to November 2, 2002, with the aim of examining the advanced technologies related to industrial boilers in the United States. The TCAPP/CATETC project is a \"bilateral market-driven climate technology transfer project\" initiated by the U.S. **Environmental Protection Agency (EPA)** and China’s State Planning Commission. The composition of the delegation is shown in Table 1. Table 1 List of the Chinese Industrial Boilers Delegation Name Title Organization Yang Qijuan Vice Secretary-General Chinese Society of Power Engineering Wei Zhihong Professor Tsinghua University Mao Jianxiong Professor Tsinghua University Zhong Lianyuan Chairman Jinan Boiler Group Co., Ltd. Xuan Yanming Chairman Nantong Wanda Boiler Co., Ltd. Xu Keqin Deputy General Manager Harbin Hongguang Boiler Group Co., Ltd. Wang Guangxi Vice Chairman Shandong Tai’an Group Company Qian Dexia Deputy General Manager Wuxi Huaguang Boiler Company Liu Xuehua Chairman Jinan Wuzhou Environmental Protection and Energy Saving Technology Co., Ltd. Mr. Mark C. Freeman from the **Energy Technology Laboratory and Ms. Jean Y. Ku from the **Renewable Energy Laboratory at the U.S. Department of Energy made comprehensive arrangements for this inspection and accompanied the Chinese delegation during the visit. Their careful arrangements, the well-organized and thoughtfully planned itinerary, as well as all their efforts for this visit were the key to the success of this expedition. Table 2 shows the schedule of the delegation’s visits. During their 12 days in the United States, the delegation visited seven industrial boiler rooms, two coal companies, and three universities ； Visited a boiler manufacturing company and an industrial boiler sales company ； In Pittsburgh, technical exchange activities took place over three full days at the University of Pennsylvania and in Clinton, New Jersey. During the exchange, many experts from various organizations, including the Energy Services Division of General Electric in the United States, the Gas Technology Institute, the University of Pittsburgh, Pennsylvania State University, Caspian University, and Foster Wheeler Company, provided the delegation with detailed explanations on various aspects. These include combustion, gasification, fluidized bed technology, emission control, system optimization, and biomass combustion technology. The places visited by the delegation were warmly received by the relevant companies and institutions. This visit left a deep impression on the delegation and achieved its intended goals. The 19 delegations learned a great deal from this field trip. However, this inspection report focuses mainly on the following aspects: new technologies related to industrial boilers ； Characteristics of industrial boiler rooms ； The quality of coal used in industrial boilers, its preparation and supply, as well as some suggestions for future cooperation between the two parties. Table 2: Itinerary of the Chinese industrial boiler delegation’s visit Date Activity details October 21: Arrival in Pittsburgh, USA October 22: Technical exchanges in Pittsburgh. It covers the Gas Technology Research Institute’s introduction to natural gas and coal-fired industrial boilers, aimed at improving efficiency and reducing emissions ； Coal gasification technology. GE presents industrial boiler combustion process optimization software as well as Novel Diognostic for online measurement of fly ash carbon content and furnace temperature distribution. On October 23, visited the coal-throwing boiler, gas-fired fire-tube boilers, and pulse-jet bag filters at NISON’s industrial boiler room in Pittsburgh ； The cogeneration plant at the regional water treatment facility in Pittsburgh AICOSAN uses a circulating fluidized bed boiler that burns solid sludge, along with a flue gas purification system. On October 24, visited the chain grate boilers, bottom-fed grate boilers, and moving grate boilers at the Bellefield boiler room of Heinz in Pittsburgh. Visit to CQ Company’s Ginger plant, as well as a technical exchange on the mixed combustion of coal and biomass in flue-fired boilers conducted by the University of Pittsburgh. On October 25, we visited the process of preparing coal for industrial boilers at C&K Energy Rawlee in Pennsylvania, as well as the vibrating grate boilers in the boiler room at Polk State Hospital. October 26–27: Weekend off. October 28: Technical exchange and visit to the boiler room at Pennsylvania State University. On October 29, visited an industrial-scale pulverized coal combustion boiler at the Houtsdale Corrections Institute in Pennsylvania, which features a furnace limestone injection and afterburner wet desulfurization system. On October 30, technical exchanges were held at Foster Wheeler in New Jersey, covering pulverized coal boilers, low-NOx burners, quick-install industrial boilers, and circulating fluidized bed boilers. On October 31, visited Powerhouse Equipment & Engineering in Delanco, New Jersey, to learn about their experience in the sales and leasing of industrial boilers. The inspection concluded in New York City on November 1st. Left the United States from New York on November 2nd. 1 New technologies related to industrial boilers 1.1 K-combustion optimization system: The MK combustion optimization system was developed in 1998 by General Electric’s Energy Services Division. This system includes a CO grid, LOI and FEGT monitors, and burner diagnostics. The features of this system are: l CO grid: continuous, on-line, and real-time monitoring of gaseous combustibles (CO) ； Multiple-point display of CO distribution in the convection channel requires no sampling, heating, reference gas, or external power supply. l LOI and FEGT monitors: enable effective optimization of the boiler and its combustion. l Burner diagnosis: Continuous online monitoring of NOx levels in the burners, with adjustments made to each burner to minimize NOx emissions. It features high sensitivity, reliability, and response capabilities, enabling effective balancing and optimization of combustion in boilers. Based on the aforementioned system, the combustion optimization system has the following features: it enables coordinated optimization among NOx, fly ash carbon content (LOI), and CO. l Improve boiler performance and reduce emissions. It enables the boiler to operate more stably and evenly, reduces slag formation, and lowers the costs of selective catalytic flue gas denitration (SCR). l can be used in pulverized coal boilers and grate boilers. 1.2 Application of the “METHANE de--NOx” technology in grate boilers: “METHANE de--NOx” is a gas recirculation technology developed by the Gas Technology Institute (GTI) in the United States to improve the efficiency of grate boilers, reduce NOx emissions, and enhance the combustion in solid fuel grates. It requires that the calorific value of the natural gas injected into the furnace of a grate boiler account for 5–25% of the boiler’s total heat load. This patented technology is suitable for upgrading existing grate boilers; it includes natural gas injection, a flue gas recirculation system, and an upper fire draft system. This system has been applied in the United States, and its advantages include the following: METHANE de--NOx can reduce NOx by 70% with no by-product emissions. For boilers that burn municipal waste, the METHANE de–NOx technology can reduce dioxin emissions by nearly 80%. The technical upgrade can be completed without interrupting operation. The specific operational improvements on site include reducing the unburned carbon in the ash ； Improving the combustion in furnaces of difficult-to-burn, high-moisture waste fuels such as sludge ； Increase the thermal efficiency of the boiler by 1–2%. l Boiler operators can gain a better understanding of boiler control under unstable conditions. 1.3 The use of the “Stoke Air Foil” (SAF) technology in grate boilers: The Energy Research Center at Lehigh University gave a brief introduction to the delegation on the “Stoke Air Foil” (SAF) system. The SAF system is an air-guided wing-shaped tube that is installed above the cross-section of the ignition zone in the coal bed, right above the grate. This patented technology was developed to improve the grate combustion in grate boilers. It is reported that the SAF system has been installed on flue gas boilers for testing, and the test results show that it can reduce the carbon content in fly ash as well as the overall excess oxygen level, thereby increasing the efficiency of the boiler by about 5–10%. 1.4 Combined combustion of coal and biomass (urban waste wood) in coal-fired grate boilers. This is a project funded by the U.S. Department of Energy (DOE). The University of Pittsburgh presented the test results on the combined combustion of coal/biomass in grate boilers. The test was conducted in a chain grate boiler located in the local district heating boiler room. Due to the low energy density and low calorific value of biomass, when the volume fraction of biomass fuel in the total mixed fuel (coal/biomass) is 50%, the thermal contribution from biomass is actually only 10%; therefore, the proportion of biomass is a key factor that affects the combined combustion process. Test results showed that, without making any modifications to the boiler, by feeding a mixture of coal and biomass into the furnace through the existing coal feeding system, the volume mixing ratio of the biomass fuel could only reach 20–40%. When the volume mixing ratio of biomass fuel is 20%, the coal/biomass mixture flows well and there are no issues with combustion. However, when the volume mixing ratio of biomass is 40%, fuel delivery problems increase, and some combustion-related issues also occur. However, when the furnace is supplied with biomass fuel through separate biomass fuel supply systems, biomass can account for a volume mixing ratio of over 40%. For the combined combustion of coal and biomass, there are still some key issues that need to be addressed, such as: Technical issues: for example, improving and solving the problem of unburned materials remaining behind the grate ； The issue of fine fly ash above the fuel bed ； The coking problem in the front furnace wall ； Large, hard slag lumps ； The emission of light and white fly ash results in an even lower opacity of the (smoke) than usual. Reduce the production costs of biomass and improve the collection, transportation, and management of biomass fuels. l Institutional issues: including positive tax incentives and policies for “green” energy. 1.5 Multi-fuel Circulating Fluidized Bed Boilers (CFB): The University of Pennsylvania in the United States is planning to build a demonstration project of a multi-fuel CFB boiler for the district heating boiler room at its campus on the East Side. It mainly demonstrates the technology for the combined combustion of agricultural and other wastes with coal. The objectives of this project are as follows: to supply heat to university campuses in a more economical manner ； Reduce air pollutant emissions (NOx, SO2, PM particles, potential trace elements), thereby helping to lower the total emissions from the heating plant in the university campus ； l Reduce the amount of agricultural products and other waste generated by universities ； l Reduce CO2 emissions by burning waste biomass fuel ； It serves as a commercially scaled test facility for the federal government and its development projects funded by it. The main technical feature of this project is that: Foster Wheeler’s CFB technology enables the combined combustion of coal/biomass to operate reliably with extremely low emissions. A compact separator can reduce the floor space required. The final superheater is located inside the furnace, which helps to minimize corrosion in future power generation applications. l A biomass fuel conveying device that facilitates the handling of biomass fuels with different properties, and can minimize odors within the plant. l Biomass storage bin with a movable bottom – ensures the fluidity of biomass fuel. The total investment for the first phase of this project is $75 million, funded by the U.S. Department of Energy (DOE), Pennsylvania**, and the University of Pennsylvania. The University of Pennsylvania is developing this multi-fuel CFB technology together with Foster Wheeler, Parsons Energy and Chemical Group, and other organizations. The feasibility study for this project will be completed in December 2002; various fuels such as coal, sludge, pig offal, cattle and sheep manure, reeds, grass, plastic, wood chips, and particleboard will be used in this CFB boiler. The boiler’s output is 200,000 pph, with steam parameters of 250 psig and 540°F. The total heat input of the boiler is 200 million Btu/hr. In terms of heat input, calculated on an energy value basis, coal accounts for 79%, while other fuels account for 21% ； By weight, coal accounts for 53%, while other fuels account for 47%. The estimated emission levels are: SO2≈0.15 Ib/MMBtn, CO≈0.2 Ib/MMBtn, NOx≈0.2 Ib/MMBtn, and dust≈0.04 Ib/MMBtn. Research and development projects related to this project are already in progress, including fuel analysis, ash characteristics, combustion properties, and computational fluid dynamics models (CFD). 1.6 Producing engineering fuel (E-fuel) from waste coal powder in coal washing ponds 22 In 1994, 50 billion tons of waste coal were stored at more than 2,000 sites in 27 states in the United States. 20–50% of the raw coal mined is discarded as coal dust and low-quality material during coal washing. According to research conducted by the University of Alabama, the 20 coal washing plants under investigation contained approximately 13.9 million tons of waste coal. Based on estimates of their coal washing capacity, it is estimated that around 5.9 million tons of coal can be recovered. The quality of the cleaned product recovered from the coal washing pool is: ash content of 4.1–11.9% ； Sulfur content: 0.6–1.5% ； Calorific value (high end): 13,100–14,900 Btu/Ib; recovery rate: 16.5–64%. In the United States, the recycling of waste coal has a long history, along with the necessary technologies and equipment for it. CQ Company has successfully developed an innovative eco-friendly synthetic fuel called “E-fuel”. E-fuel is a competitively priced fuel that combines coal with biomass and industrial by-products. These biomasses and industrial by-products include sludge from paper mills, while coal is recycled waste coal. This technology is a process for recovering waste coal from the waste coal powder in the coal washing pool. These coal washing tanks usually result in a relatively high ash content in the coal, ranging from 30 to 50%, due to the presence of suspended slag. The process commonly used for recovering coal powder from the coal washing tank and the process circuit equipment used in coal washing plants to wash raw coal into clean pulverized coal are the same. But the structure and operating parameters of the circuit can be different. For example, when the soil content is high, the proportion of fine coal powder is large, and the supply quality is variable, more attention must be paid to process monitoring and control. After cleaning, the process of producing E-fuel involves the following steps: dehydration/drying of coal powder, compression/molding, further dehydration/addition of binders, inclusion of other fuels—biomass and industrial by-products, screening/storage, weighing/sampling/laboratory testing, and finally, the use of E-fuel in coal powder boilers and grate boilers. Since E-fuel is made up of approximately 70% coal, 25% paper mill sludge, and 5% plastic waste, which are compressed into small balls using a mold with a diameter of about 1.5–1 inch and a length of less than 1.5 inches, it can be used as a clean fuel in chain grate boilers. According to CQ Company, tests have shown that using E-fuel can reduce dust emissions by 52% compared to burning coal alone, while emissions of SO2 and NOx are reduced by approximately 40% and 19%, respectively. Currently, in the United States, in an effort to reduce coal usage, there are about 30 plants that specialize in producing coal-based synthetic fuels. Their total annual production capacity is around 13.5 million tons. Among these are seven plants that manufacture E-fuel coal, which together produce 1.5 million tons of such coal each year. Additionally, the University of Pennsylvania’s Energy Institute also carried out a project to convert waste coal powder from coal washing tanks into coal water slurry (CWSF) for use in stoker furnaces; this project was funded by the U.S. Department of Energy (DOE) and the Pennsylvania Energy Development Authority. The waste coal powder in the coal washing tank is collected in 4 locations, where it is cleaned and processed into a water-coal slurry (CWSF) with a low solid concentration, which is then burned together with coal in an industrial boiler. CWSF is characterized by a 41–10% reduction in ash content, a slight increase or no change in sulfur content, ranging from 1.1–1.4%, a recovered calorific value of about 88%, and a solid concentration of 56–61%. Water-coal slurry can remain in a stable state for more than seven days at 100–200 CP and 100s–1. The combustion performance is as follows: when burned in combination with coal at 20% CWSF (heat value), the burnout rate ranges from 90 to 95.6%, whereas when burned with 100% coal powder, the burnout rate is 90.4%. When NOx emissions are reduced by about 8–13%, there is no significant decrease in burnout degree. 2 Characteristics of industrial boiler rooms During the inspection, the delegation visited boiler rooms for district heating in seven areas. These boilers include almost all types of grate boilers, such as stoker-chain grate boilers ； Back-and-forth grate and bottom-fed grate ； Oil, gas, and fire-tube boilers, as well as industrial-scale pulverized coal boilers. Table 3 is a summary of the characteristics of these boiler rooms. Table 3 Characteristics of Industrial Boiler Rooms in the United States 23 Boiler Room Name Characteristics NIOSH One stoker-fired grate boiler (with a steam capacity of 55,000 IB/hr) and two gas-fired fire-tube boilers (700 hp), which provide heating from October of one year to May of the following year. Cleaning and maintenance are carried out once a month each year. All boilers are automatically controlled by computers, and there are only four operators in the entire boiler room. The stoker grate boiler was put into operation in 1980, and it still looks as good as new today. Its thermal efficiency can remain above 83%. This boiler is equipped with a flue gas recirculation and updraft system, as well as pulse-jet bag filters for dust removal, which improves the burn rate of fly ash and reduces emissions of NOx and dust. ALCOSAN is a boiler room that generates energy by burning waste. There are two CFB boilers equipped with flue gas purification systems, all of which burn solid sludge, a by-product of the ALCOSAN water treatment plant. 75–80 dry tons of dried sludge product are produced per day. Each CFB boiler has a steam output of 26,400 Ib/hr, and its designed capacity for handling sludge is 79 dry tons per day. The first and second streams of slurry contain 20% solids, corresponding to 13 dry tons per day, and 70% solids, corresponding to 5 dry tons per day, respectively. The dry-base calorific value of the solid sludge is 7,000 Btn/Ib. The superheated steam generated by the boiler is used for power generation, and the output of the steam turbine generator is 1250 KW. HEINE has two chain grate boilers with a capacity of 60,000 Ib/hr and two with a capacity of 40,000 Ib/hr. This boiler room uses typical coal for American grate boilers. The characteristics of this coal are as follows: ash content of 6–9%, moisture content of 6–8%, sulfur content of 0.7%, and calorific value of 12,874 Btu/Ib (HHV). The particle size distribution ranges from 1/4 to 3-4 inches, with less than 10% of the particles being smaller than 1/4 inch. To improve the thermal efficiency of the boiler and reduce emissions, 10% natural gas was used. BELLEFIELD is a very old boiler room, built in the early 1900s, with seven boilers. Two fuel/gas boilers, each with an output of 150,000 Ib/hr ； Two lower-fired grate boilers, each with an output of 60,000 Ib/hr ； Three chain grate boilers, each with an output of 10,000 Ib/hr. The coal in this boiler room is typical American grate boiler coal, supplied under a contract for coal intended for grate boilers. This boiler room is located behind Pittsburgh’s educational and cultural center, the Carnegie Museum, and it provides heating for the buildings of universities and museums in this area. Many boilers have been in operation for 20–52 years (the oldest bottom-fed grate boilers were built in 1938), but the reason they are still able to operate with high efficiency and low emissions is due to the high quality of management in these boiler rooms, strict and standardized operating procedures and timely maintenance, as well as the use of high-quality coal intended for industrial boilers. At POLK STATE Hospital, there are three reciprocating grate boilers in this boiler room, each equipped with a 300KW combined cycle generator; each boiler generates steam at a rate of 35,000 Ib/hr. The steam at a pressure of 180 Psig is used for power generation, while the steam at a pressure of 40–50 Psig is used for heating/cooling purposes in the hospital. The thermal efficiency of the boiler is 75–85%. These boilers use typical coal for American grate boilers, which is supplied by coal suppliers in strict accordance with the coal quality specifications specified in the contract. Penn State University has two boiler rooms, one in the east part of the campus and another in the west part. They supply heat to a heating area of 1.2 million square feet. The output of the combined power generation systems for the two units is 2.5 MW and 3.5 MW respectively. In the western boiler room, there are four reciprocating grate boilers, each with a steam output of 50 t/h. These boilers were installed between 1961 and 1968. Subsequently, to improve the thermal efficiency of the boilers and reduce emissions, many new technologies were adopted for them, including natural gas injection, updraft systems, bag filters, online monitoring, and computerized control systems. There are two oil/gas boilers in the eastern boiler room, and these boilers are operated by an automatic remote control system located in the western boiler room. The HOUTZDALE CORRECTIONS INSTITUTE is equipped with two industrial-scale pulverized coal boilers, along with a flue gas desulfurization system that utilizes calcium injection in the furnace and tail gas humidification; this system achieves a desulfurization efficiency of over 90%, and bag filters are used to collect dust. The boiler was originally designed as a horizontal fuel/gas boiler; to reduce fuel costs, it was converted into a horizontal coal powder boiler in 1994/1995. Each type used had a sulfur content of 1.2%, and its SO2 emission level was 0.81 Ib/MMBtu (the **SO2 emission standard in the United States is 1.2 Ib/MMBtu). 3 Preparation and supply of coal for grate boilers In the United States, all coal used in grate boilers is referred to as “grate coal”. “\"Grate coal\" is coal that has been washed and graded to meet specific quality requirements; different types of grate boilers have varying requirements regarding the coal’s properties, calorific value, and particle size distribution. The quality of coal is an important factor in ensuring high thermal efficiency and low emissions in boilers; coal suppliers must prepare and supply coal to different users in accordance with the technical specifications specified in the coal procurement contracts. C&K Energy/Rawlee Fuel Company (RFI) is one such coal supplier, and the delegation visited the company. Its production capacity is 200 tons per hour. The price of the \"grate coal\" it provides is 38–40 dollars per ton. The delegation witnessed the entire process of producing \"grate coal\", including the processes and equipment for coal washing, screening, and grading. It was also learned how RFI prepares and supplies \"bunker coal\" to the boiler room at the University of Pennsylvania. During the visit to the Heinz boiler room, the delegation learned about the contracts through which suppliers supply \"grate coal\" to users of grate boilers; this serves as an example of how strict controls are exercised in the United States over the quality of \"grate coal\" in order to ensure high efficiency and low emissions from boilers. All coal supplied to industrial boiler rooms is provided in accordance with a coal supply contract, which specifies the technical requirements for such coal, including specifications regarding coal analysis, particle size, calorific value, and other factors. To ensure that the coal delivered meets the required standards in both chemical and physical aspects, samples of the coal brought to the boiler room must be taken for testing. It is specified to collect 1 to 2 coal samples per day; on weekends, the coal samples collected during that week are combined and sent to the laboratory for testing. “The “grate coal” supplier can observe any sampling process. The coal sample test results can be provided to the “grate coal” supplier upon request. Weekly, the chemical and physical properties of the supplied coal shall be evaluated on an \"as received\" basis to determine whether they meet the coal quality requirements specified in the contract as shown in Table 4. Table 4: Technical specifications, coal analysis, and particle size requirements for the “grate coal” supplied to the Heinz boiler room. Parameter: Technical specifications (on an ash-based basis). Moisture: Not more than 8%. Sulfur: Not more than 0.7%. Ash content: 6–9%. Higher heating value: 12,700–13,300 Btu/Ib, with an average of at least 13,000 Btu/Ib. Ash melting point: 2,700oF or higher. Volatile matter: 35–45%. Fixed carbon: 45–55%. Expansion index: Not more than 4. Particle size: 3/4” × 1/4”; no more than 8% of particles may be smaller than 1/4”. 40%–60% of the coal particles should pass through a 3/4” sieve while remaining on a 1/4” sieve. The coal purchase contract also specifies penalties in case the coal quality does not meet the requirements set out in the contract. For example, based on the results of weekly sampling tests, if the sulfur content in the coal exceeds 0.75% of the specified limit, and including the repeatability error of the laboratory test data which exceeds 0.005%, then the coal price shall be reduced by 5% based on the contract price. If the test results show that the calorific value of the coal is below 12,500 Btu/Ib, then the coal price shall be reduced by 20% based on the contract price. If the moisture content of coal reaches 10% or higher, the price of coal decreases by 2% for every 1% increase in moisture content. Thanks to the strict provisions of the contract, coal suppliers prepare coal for each individual customer in strict accordance with the quality requirements specified in the contract, thereby ensuring the quality of the coal supplied to the furnaces and the performance of the boilers. 4 Conclusions and Future Cooperation Opportunities 25 4.1 China has 500,000 coal-fired boilers, most of which are grate boilers, but they have relatively low thermal efficiency and high emissions. In the United States, there are currently 3,000 grate boilers in use, which feature high thermal efficiency and low emissions; many of these boilers have been in operation for many years. Through this inspection, the delegation saw all types of grate boilers found almost throughout China, including coal-throwing chain boilers, chain grate boilers, bottom-fed grate boilers, and vibrating grate boilers, which all have similar designs. But why is there such a large difference in the performance of these grate boilers between the two countries? From this inspection, we believe the following points should be learned: (1) The United States uses high-quality \"grate coal\" in its grate boilers, whereas in China, grate boilers use raw coal extracted from coal mines; this coal has a high proportion of fines, which is not suitable for efficient combustion and emission control in grate boilers. This is the fundamental reason why most boilers in China are inefficient and emit high levels of pollutants. To improve the performance of grate boilers in China, it should learn from the United States’ experience by establishing technical standards for grate coal, upgrading the systems for its preparation and supply, and reforming the coal supply framework. (2) Well-trained, highly skilled boiler operators, along with strict standardized management, operation, and timely maintenance, are another key factor in ensuring that the boiler room is in good condition. Even for old boilers that have been in use for many years, proper management, operation, and maintenance can help extend their service life while maintaining good performance. (3) Many grate boilers are old-fashioned models designed many years ago; in the United States, many of these boilers are extremely old and have been in use for decades. With increasingly strict emission regulations and the development of more sophisticated control systems, many boiler rooms have been upgraded with flue gas cleaning systems such as natural gas injection, flue gas purification, bag filters, and computerized control systems, enabling these older systems to function more effectively. This is also why many old boiler rooms in the United States have been able to remain technically advanced. If China can, based on its own conditions, learn the technologies and experiences of the United States as described above, we believe that the performance of industrial boilers in China can be improved rapidly; the thermal efficiency of these boilers can reach international standards, and their emissions can meet the required limits. 4.2 The delegation learned about many new technologies applicable to industrial boilers, which are described in the second paragraph of this report. There are many opportunities in the country to test, demonstrate, transfer, and utilize these new technologies. To improve the performance of boilers, the MK combustion optimization system is very useful for monitoring, diagnosing, and optimizing the combustion performance of boilers. China and the United States should find a way to cooperate in demonstrating and transferring these technologies to China. Injecting a small amount of natural gas into the furnace can **reduce NOx emissions from grate boilers and improve their thermal efficiency**. Currently, the massive natural gas pipeline project in China to transport gas from the west to the east is under construction; once completed, many provinces in eastern China will be able to receive gas supplies. Therefore, the “METHANE” de—NOx technology could potentially be used in Chinese grate boilers. Building on the industrial boiler testing site project in Huairou, Beijing, it is necessary to find ways to conduct tests and demonstrations of this technology. The “Storker Air Foil” (SAF) technology is a very attractive option for grate boilers; it can also be combined with the TCAPP/CATETC pilot projects for testing, demonstration, and transfer to China. Regarding the TCAPP/CATETC pilot project, the district heating plant in Huairou, Beijing, has been selected as the test site. We recommend testing the “Storker Air Foil” at the Huairou district heating plant as well, and comparing the test results before and after; this can serve as a basis for further evaluation, demonstration, and the transfer of SAF technology. It is highly significant to carry out combined combustion of coal and biomass in grate boilers, as China not only has the largest number of such boilers but also abundant biomass energy resources. It is estimated that in 2000, China had a total of 437 Mtec of biomass energy per year, of which 240 Mtec came from crop residues. Since the U.S. project on co-combustion of coal and biomass, funded by the U.S. Department of Energy (DOE), has achieved some useful results, we hope to find a way to strengthen ties with our American partners and collaborate on the development of coal and biomass co-combustion technology. To improve the performance of industrial boilers in China and reduce emissions, high-quality \"grate coal\" must be used. Therefore, China’s coal production and supply system must be reformed. To achieve this goal, China should build on the experimental results of TCAPP and continue to work together with the U.S. EPA and DOE to develop the “Chinese grate coal” system. China’s \"Clean Coal Technology Engineering Center\", coal companies, and boiler experts should work together to develop a proposal regarding \"grate coal\" in China. By drawing on the experience of \"grate coal\" use in the United States as well as relevant coal quality standards, they should explore a coal supply system and technical requirements for \"Chinese grate coal\" that are suitable for China’s boiler efficiency and emission levels. Furthermore, recommendations should be made regarding the choice of \"Chinese grate coal\" for use, as well as the modifications to grate boilers necessary to accommodate it. If this proposal is approved and funded, the next step in this project is to select a grate boiler on which to conduct tests using \"Chinese grate coal\" (for TCAPP, the location for such tests could be the heating plant in Huairou District, Beijing). 5 Thank you. The visit by the Chinese industrial boiler delegation was made possible through the invitation and support of the U.S. Environmental Protection Agency (EPA). Mr. Mark C. Freeman from the **Energy Technology Laboratory and Ms. Jean Y. Ku from the **Renewable Energy Laboratory at the U.S. Department of Energy took careful care of the delegation’s visits and accompanied them throughout the entire process. The delegation was also warmly received by the following organizations: NIOSH boiler room, ALCOSAN water treatment plant, Heinz boiler room, Bellefield boiler room, Ginger Hill plant of CQ Company, Pennsylvania University, Houtzdale Corrections Institute boiler room, Lehigh University, Foster Wheeler Energy Company, and Powerhouse Equipment Engineering Co. The delegation takes this opportunity to express its sincere gratitude to the aforementioned organizations and individuals! Thanks to their work and efforts, this inspection was a **success!**